553 research outputs found

    Produção de lipase a partir de leveduras não convencionais isoladas do bagaço de caju

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    As lipases (E.C. 3.1.1.3) são uma classe de enzimas que catalisam a hidrólise dos triglicerídeos de ácidos gordos livres e glicerol. Essas enzimas encontram uma grande aplicação nas indústrias de alimentos, detergentes, cosméticos, síntese orgânica e farmacêutica. Neste trabalho, as leveduras Candida tropicalis e Meyerozyma caribbica isoladas do bagaço de caju foram testadas quanto à sua capacidade de produção de lipase. As fermentações foram conduzidas em agitador rotatório a 30 °C e 170 rpm. A medida da atividade foi feita através da hidrólise com o pNFL (p-nitrofenil laurato). Para a produção da enzima foi utilizado um meio de cultura contendo resíduos agroindustriais, nomeadamente melaço 10 g/L, milhocina 4 g/L, águas russas 1,0 % (v/v). A atividade do sobrenadante da C. tropicalis foi 233 ± 10 U/L e da M. caribbica foi 146 ± 7,30 U/L em 24 h de fermentação. Esses resultados mostram o potencial dessas estirpes para a produção da enzima lipase a partir de resíduos agroalimentares

    Produção de lipase a partir de Candida rugosa NRRL Y-95 utilizando meio de cultura contendo resíduos agroindustriais

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    As lipases (E.C. 3.1.1.3) são um grupo de enzimas capazes de catalisar a hidrólise da ligação éster de triacilgliceróis, gerando ácidos graxos livres e glicerol. As lipases microbianas são muito utilizadas nas aplicações industriais nas áreas de alimentos, síntese orgânica e farmacêutica. Neste trabalho, visando à produção de lipase a partir da levedura Candida rugosa foram utilizados meios de cultura alternativos compostos por melaço, milhocina e águas russas. As fermentações foram conduzidas em agitador rotatório a 30 °C e 170 rpm. Testaram-se quatro meios contendo diferentes combinações dos resíduos acima mencionados. O meio contendo melaço 10 g/L, milhocina 4 g/L e águas russas 1,0 %(v/v) foi o que propiciou a produção de enzima com maior atividade intracelular 269 ± 10 U/L frente ao substrato pNFL (p-nitrofenil laurato). Esses resultados demonstram que o referido meio alternativo contendo resíduos agroindustriais é adequado para a produção de lipase

    The yeast-like fungus Aureobasidium thailandense LB01 produces a new biosurfactant using olive oil mill wastewater as an inducer

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    In this study, the biosurfactant production by an Aureobasidium thailandense LB01 was reported for the first time. Different agro-industrial by-products (corn steep liquor, sugarcane molasses, and olive oil mill wastewater) were evaluated as alternative low-cost substrates. The composition of the culture medium was optimized through response surface methodology. The highest biosurfactant production (139 ± 16 mg/L) was achieved using a culture medium containing yeast extract (2 g/L); olive oil mill wastewater (1.5%, w/w); glucose (6 g/L) and KH2PO4 (1 g/L) after 48 h of fermentation. The partially purified biosurfactant exhibited a critical micelle concentration of 550 mg/L, reducing the surface tension of water up to 31.2 mN/m. Its molecular structure was found to be similar to a lauric acid ester. The biosurfactant exhibited a better performance than the chemical surfactant sodium dodecyl sulfate (SDS) in oil dispersion assays, thus suggesting its potential application in bioremediation.The authors acknowledge the Biotechnology laboratory (UFC) and Doctor Tatiana Nunes, as well as CAPES, CNPq and FUNCAP for the financial support. This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and under the scope of the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the Project MultiBiorefinery − Multi-purpose strategies for broadband agro-forest and fisheries by-products valorisation: a step forward for a truly integrated biorefinery (POCI-01-0145-FEDER-016403). The authors also acknowledge financial support from BioTecNorte operation (NORTE-01-0145-FEDER-000004) and Project BioInd − Biotechnology and Bioengineering for improved Industrial and Agro-Food processes (NORTE-07–0124-FEDER-000028) funded by the European Regional Development Fund under the scope of Norte2020 − Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

    Determinantes espaciais e socioeconômicos do suicídio no Brasil: uma abordagem regional

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    Suicide is considered a public health issued by the World Health Organization. Suicide is amongst the ten most frequent causes of death in all ages, in addition to being the second or third cause of death between 15 and 34 years of age. Estimates show that for every suicide there are at least ten suicides attempts that require medical attention and for every suicide attempt recorded, four are not known. The aim of this paper is to analyze the socioeconomic determinants of suicide rates for Brazilian micro-regions, taking into account spatial aspects of the problem. The hypothesis of this paper is that there is a "spatial contagion effect" for suicide, that is to say, the neighborhood suicide rates are an important determinant of the regional suicide rate. This is achieved by the use of spatial econometrics techniques to assess whether there is spatial dependence for suicide rates in micro-regions.A Organização Mundial da Saúde avalia o suicídio como um problema de saúde pública, estando entre as dez causas mais frequentes de morte, além de ser a segunda ou terceira causa de morte entre 15 e 34 anos de idade. Estimativas mostram que para cada suicídio, existem pelo menos dez tentativas suficientemente sérias que exigem atenção médica e para cada tentativa de suicídio registrada, existem quatro não conhecidas. O objetivo desse artigo é avaliar os determinantes socioeconômicos das taxas de suicídio por microrregiões brasileiras, levando em consideração aspectos espaciais do problema. A hipótese desse artigo é que existe um "efeito contágio" espacial para o suicídio, ou seja, as taxas de suicídio dos vizinhos de uma microrregião são importantes determinantes do comportamento dessa variável em outra microrregião. Para tal, são usadas técnicas de econometria espacial que permitem avaliar se existe dependência espacial entre as taxas de suicídio das microrregiões

    COMFORT SEAT MODULE - FIRST CLASS COMFORT FOR ALL

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    The Comfort Seat Module (CSM) is a project developed in the scope of the EDAM focus area of the MIT – Portugal program, within the Product Design and Development course. The team members involved in the project come from several Engineering backgrounds and includes research students and engineering professionals, from different geographical origins. In this project the team had the purpose of designing and developing a solution, from idea into concept and then onto a valid product that could potentially be produced and even marketed. In parallel, the objective was to train the product development competences and team’s working skills as much as possible, considering the physical distance between the team members.info:eu-repo/semantics/publishedVersio

    Sustainable lipase production by Diutina rugosa NRRL Y-95 through a combined use of agro-industrial residues as feedstock

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    The potential use of alternative culture media towards the development of a sustainable bioprocess to produce lipases by Diutina rugosa is clearly demonstrated. First, a synthetic medium containing glucose, peptone, yeast extract, oleic acid, and ammonium sulfate was proposed, with lipase activity of 143 U/L. Then, alternative culture media formulated with agro-industrial residues, such as molasses, corn steep liquor (CSL), and olive mill waste (OMW), were investigated. An experimental design was conducted, and only CSL concentration was found to have a positive effect in lipase production. The highest lipase activity (561 U/L) was produced on a mixture of molasses (5 g/L), CSL (6 g/L), OMW (0.5\\% v/v), 0.5 g/L of ammonium sulfate, and 3 g/L of peptone at 24 h of cultivation. Lipase production was also carried out in a 1-L bioreactor leading to a slightly higher lipase activity at 24 h of cultivation. The semi-purified enzyme exhibits an optimum temperature and pH of 40 \textdegreeC and 7.0, respectively. Finally, the media cost per unit of lipase produced (UPC) was influenced by the medium components, specially by the inducer used. The lowest UPC was obtained when the agro-industrial residues were combined and used at the improved concentrations.The study is funded by CAPES, CNPq, and FUNCAP (from Brazil) for the financial support that made this work possible. In addition, the study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, the BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte, and the Project LIGNOZYMES (POCI-01-0145- FEDER-029773).info:eu-repo/semantics/publishedVersio

    Diferenciais de produtividade do trabalho no Brasil e o processo de catching up

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    Este artigo realiza testes econométricos sobre séries de produtividade do trabalho da indústria de transformação de estados e regiões brasileiros no período 1985-2000. Aplica-se o teste de Perron nos dados da Pesquisa Industrial Mensal do Instituto Brasileiro de Geografia e Estatística (IBGE). Diferentemente de outros estudos, a data da quebra não é estabelecida de maneira exógena, mas adota-se um método endógeno. Além disso, o artigo investiga a existência de um processo de catching up do nível de produtividade entre estados do Sudeste, Regiões Nordeste e Sul e o Brasil. Os resultados mostraram que as séries não são caracterizadas pela presença de uma raiz unitária, além de apresentarem trajetórias determinísticas diferenciadas de acordo com o período considerado

    Poly(dimethyl siloxane) surface modification with biosurfactants isolated from probiotic strains

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    Depending on the final application envisaged for a given biomaterial, many surfaces must be modified before use. The material performance in a biological environment is mainly mediated by its surface properties that can be improved using suitable modification methods. The aim of this work was to coat poly(dimethyl siloxane) (PDMS) surfaces with biosurfactants (BSs) and to evaluate how these compounds affect the PDMS surface properties. BSs isolated from four probiotic strains (Lactococcus lactis, Lactobacillus paracasei, Streptococcus thermophilus A, and Streptococcus thermophilus B) were used. Bare PDMS and PDMS coated with BSs were characterized by contact angle measurements, infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The influence of the surface modifications on the materials blood compatibility was studied through thrombosis and hemolysis assays. The cytotoxicity of these materials was tested against rat peritoneal macrophages. AFM results demonstrated the successful coating of the surfaces. Also, by contact angle measurements, an increase of the coated surfaces hydrophilicity was seen. Furthermore, XPS analysis indicated a decrease of the silicon content at the surface, and ATR-FTIR results showed the presence of BS characteristic groups as a consequence of the modification. All the studied materials revealed no toxicity and were found to be nonhemolytic. The proposed approach for the modification of PDMS surfaces was found to be effective and opens new possibilities for the application of these surfaces in the biomedical field.Contract grant sponsors: Portuguese Science and Technology Foundation (Fundacao para a Ciencia e Tecnologia-FCT; BIOSURFA-PTDC/SAU-BEB/73498/2006 project

    An Efficient and Layout-Independent Automatic License Plate Recognition System Based on the YOLO detector

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    This paper presents an efficient and layout-independent Automatic License Plate Recognition (ALPR) system based on the state-of-the-art YOLO object detector that contains a unified approach for license plate (LP) detection and layout classification to improve the recognition results using post-processing rules. The system is conceived by evaluating and optimizing different models, aiming at achieving the best speed/accuracy trade-off at each stage. The networks are trained using images from several datasets, with the addition of various data augmentation techniques, so that they are robust under different conditions. The proposed system achieved an average end-to-end recognition rate of 96.9% across eight public datasets (from five different regions) used in the experiments, outperforming both previous works and commercial systems in the ChineseLP, OpenALPR-EU, SSIG-SegPlate and UFPR-ALPR datasets. In the other datasets, the proposed approach achieved competitive results to those attained by the baselines. Our system also achieved impressive frames per second (FPS) rates on a high-end GPU, being able to perform in real time even when there are four vehicles in the scene. An additional contribution is that we manually labeled 38,351 bounding boxes on 6,239 images from public datasets and made the annotations publicly available to the research community
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